9Ouyang YQ,Zhang Q. A study on personal mode of delivery among Chinese obstetrician-gynecologists,midwives and nurses[J].{H}Archives Of Gynecology and Obstetrics,2013,(01):37-41.
10Lumbiganon P,Laopaiboon M,Gü lmezoglu AM. Method of delivery and pregnancy outcomes in Asia:the WHO global survey on maternal and perinatal health 2007-2008[J].The Lancet,2010,(9713):490-499.